The former New York mayor supports abortion rights but has also said he would appoint Supreme Court justices like John Roberts and Samuel Alito, whose votes proved crucial in yesterday’s 5-4 ruling.

The partial-birth procedure is rare but Democrats were quick to warn that the ruling would be first in a series of anti-abortion rulings. Obama said he was concerned that yesterday’s decision will “restrict a woman’s right to choose.”

Democrats were particularly upset that the ruling reversed a 2000 decision in which the court struck down state bans on the procedure. “It is precisely this erosion of our constitutional rights that I warned against when I opposed the nominations” of Roberts and Alito, Clinton said.

The court’s decision – on appeals of rulings in several states, including New York, that struck down the ban – had been expected to be the most controversial and most important of the court’s term.

In yesterday’s decision by Justice Anthony Kennedy, the court said the 2003 federal law banning partial-birth abortions does not violate Roe vs. Wade because it does not place an undue burden on a woman’s right to an abortion.

The law says doctors who perform procedure – by removing a fetus partially from a woman’s uterus and aborting it – can be jailed for up to two years. Leading the court’s dissenters, Justice Ruth Bader Ginsburg said the “alarming” decision “cannot be understood as anything other than an effort to chip away at a right declared again and again by this court.”